Modeling polyethylene-solvent mixtures with the Sanchez-Lacombe equation

The Sanchez-Lacombe equation of state was used to model cloud-point isother ms of two systems of polyethylene in ethylene and in one system of polyethy lene in n-hexane. The three polyethylene samples examined were very dissimi lar in average molar mass and polydispersity. Alternative solvent parameter sets were considered. Polymer parameters were obtained by fitting pure pol yethylene volumetric data using an additional volume shift coefficient. Exc ellent agreement with the experimental cloud-point-data could be achieved f or all three systems mentioned above. Henry's constants for ethylene in pol yethylene were also well matched by the same parameter sets. (C) 2001 Elsev ier Science BN. All rights reserved.